the warm/hot steam is condensing onto the cold ceilings and walls and forming water droplets. if your ventiation is good to vent out the warm moist steam...then all I can figure is your walls ans ceiling are not sufficiently insulated. perhaps you can solve your problems with the moisture daming your drywall walls and ceilings is to paint them with a couple of good coats of semi gloss paint. others might offer other observations on your problems and some solutions. good luck LJ